User:Atcovi/Science/The Effect of Common Antibiotics on Bacterial Growth

The two bacteria being tested in this experiment are Staphylococcus epidermidis, a gram-positive bacterium found in the human flora (skin), and Bacillus cereus, is a gram-positive bacterium normally found in the environment, an example being the soil, and many foods. Both bacteria are capable of causing harm to humans.

An antibiotic is a powerful medicine that afflicts harm or damage, usually to bacteria. Antibiotics, in order to kill their targetted bacteria, either stop the targetted bacteria from reproducing or they kill the bacteria. An example is that the antibiotic, Penicillin, works by preventing the targetted bacteria from making a cell wall.

Research into how common antibiotics can affect bacterial growth is important in the field of medicine. Workers who work in the medical field, such as doctors, may benefit from this laboratory experiment by observing which antibiotic is most effective or least effective. This research can greatly help day-day citizens, who, when the time comes, will be of in need of antibiotics to fight harmful bacteria damaging their bodies.

In the investigation, the antibiotics, Tetracycline, Erythromycin, Penicillin and Streptomycin, was the independent variable and the zone of inhibition was the dependent variable. The control in this experiment is the unlabelled circle in the center while the constants were the antibiotics and time. If the antibiotics are placed into the two different bacteria: Staphylococcus epidermidis and Bacillus cereus, then the bacterial growth in the Bacillus cereus will be less than the Staphylococcus epidermidis.

Results/Analysis
As displayed in the data table and the bar group above, the antibiotic with the greatest effect in the Bacillus cereus was the Tetracyclin while the antibiotic with the greatest effect in the Staphylococcus epidermidis was the Erythromycin. The antibiotics had an even effect on both bacteria.

Conclusion
My hypothesis, "If the antibiotics are placed into the two different bacteria: Staphylococcus epidermidis and Bacillus cereus, then the bacterial growth in the Bacillus cereus will be less than the Staphylococcus epidermidis", was not supported as the Tetracylin and Streptomycin had more effect on the Bacillus cereus while the Penicillin and the Erythromycin had more effect on the Staphylococcus epidermidis--therefore, making the common antibiotics having an even effect on the bacteria.

An error could've occurred due to several factors, such as oxygen-exposure, incorrect recording, temperature changes, and such. An unexpected result in this experiment was found within the recording of the antibiotic, Erythromycin, and its effect on the bacterium, Staphylococcus epidermidis. The Erythromycin scored a whopping 51.4 in its tallying, raising concerns about its legitimacy.